I just used graph paper and the dimensions I wanted (7' high so I could stand up and 10' diameter so there'd be plenty of room for two people and gear) used 8 panels, studied quite a few picures of other tipis on the web and started sewing, bought the materials, cut stuff and sewed it togehter. A background in sewing helps. Good luck!

jmden were did you buy the materials for your tent and how did you water proof the seams

I get the seconds, cause I really don't care if it's pretty. But, I've never figured out why why I've purchased has been a second. Don't see any color variation, or issues with waterproofing, etc.

McNett makes a product called SilNet. Since the fabric is silicone impregnated, you have to use a silicone product to seam seal. Apparently regular seam sealers won't work.

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In the beginning God created the heavens and the earth. Genesis 1:1

"And can the liberties of a nation be thought secure when we have removed their only firm basis, a conviction in the minds of the people that these liberties are the gift of God?" Thomas Jefferson - Notes on the State of Virginia

I like to use my Goretex Bivy bag over my mummy bag with a .mil poncho stretched over some fiberglass tent poles place in the corner grommets (sort of in an X fashion. It works great, stays low to the ground (does not get blown away by the wind) and helps keep heatable space to a minimum.